A novel ring fiber laser based on Er-doped photonic crystal fiber (EDPCF) is demonstrated. EDPCF is used as gain
medium to implement stable CW operation. The laser output wavelength can be continuously tuned over the range from
1529 to 1535 nm by adjusting the polarization state of the light inside the cavity. Stable dual-wavelength CW operation
is also observed with proper settings of the intracavity polarization controllers. The laser stability in terms of the output
power and the operation wavelength is characterized, and less than ±0.05 dB power fluctuation as well as 18 pm
wavelength perturbation are obtained.